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BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Advertising Costs and Expenses & Severance Costs and Expenses (Details) (USD $)	12 Months Ended			1 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2012 employee
Schedule of Accrued Severance Liability By Segment [Line Items]
Advertising costs and expenses	$ 26,700,000us-gaap_AdvertisingExpense	$ 28,200,000us-gaap_AdvertisingExpense	$ 28,200,000us-gaap_AdvertisingExpense
Prepaid advertising	142,000us-gaap_PrepaidAdvertising	19,000us-gaap_PrepaidAdvertising
2012 Restructuring Plan
Schedule of Accrued Severance Liability By Segment [Line Items]
Approximate workforce reductions (in positions)				330
Mohegan Sun
Restructuring Reserve [Roll Forward]
Balance, September 30, 2013	1,417,000
Cash payments	(1,401,000)
Balance, September 30, 2014	$ 16,000